[Numpy-discussion] performance matrix multiplication vs. matlab

[Vicente Sole]

Quoting Bruce Southey <bsouthey at gmail.com>:

> On 01/18/2010 12:47 PM, Vicente Sole wrote:
>> Quoting Bruce Southey <bsouthey at gmail.com>:
>>
>>>
>>> If you obtain the code from any package then you are bound by the terms
>>> of that code. So while a user might not be 'inconvenienced' by the LGPL,
>>> they are required to meet the terms as required. For some licenses (like
>>> the LGPL) these terms do not really apply until you distribute the code
>>> but that does not mean that the user is exempt from the licensing terms
>>> of that code because they have not distributed their code (yet).
>>>
>>> Furthermore there are a number of numpy users that download the numpy
>>> project for further distribution such as Enthought, packagers for Linux
>>> distributions and developers of projects like Python(x,y). Some of these
>>> users would be inconvenienced because binary-only distributions would
>>> not be permitted in any form.
>>>
>>
>> I think people are confusing LGPL and GPL...
> Not at all.
>
>>
>> I can distribute my code in binary form without any restriction   
>> when using an LGPL library UNLESS I have modified the library itself.
>
> I do not interpret the LGPL version 3 in this way:
> A "Combined Work" is a work produced by combining or linking an
> Application with the Library.
> So you must apply section 4, in particular, provide the "Minimal
> Corresponding Source":
> The "Minimal Corresponding Source" for a Combined Work means the
> Corresponding Source for the Combined Work, excluding any source code
> for portions of the Combined Work that, considered in isolation, are
> based on the Application, and not on the Linked Version.
>
> So a binary-only is usually not appropriate.
>

You are taking point 4.d)0 while I am taking 4.d)1:

"""
1) Use a suitable shared library mechanism for linking with the  
Library. A suitable mechanism is one that (a) uses at run time a copy  
of the Library already present on the user's computer system, and (b)  
will operate properly with a modified version of the Library that is  
interface-compatible with the Linked Version.
"""

If you are using the library as a shared library (what you do most of  
the times in Python), you are quite free.

In any case, it seems I am not the only one seeing it like that:

http://qt.nokia.com/downloads

The key point is if you use the library "as is" or you have modified it.

Armando